Consolidated metallic fiber article



c. F lELD March 3, 1927.

' CONSOLIDATED METALLIC. FIBER ARTICLE Filed June '7, 1924 r, INVENZI'ORLr'ory Field M ATTORNEY CROSBY FIELD, OF BROOKLYN, NEW YORK, ASSIGNOR TOGRAY PRODUCTS, INC., A CORPORATION OF NEW YORK.

CONSOLIDATED METALLIC FIBER ARTICLE.

Application filed June 7,

My present invention relates to articles made by subjecting metalstrands or fibers to high pressures in a suitable mold. The preferredmaterial is what is knownjas metal W001, preferably medium s ze as, formtance, what is known in the trade as No. 0 metal wool, although thefiner gauges such as N o. 00 or No. 000, or the largergauges such asNos. 1, 2 and 3, may be employed for special purposes.- Preferably, themetal wool used is cut from copper or bronze wire, although other metalsmay be preferable for certain purposes. One material which I haveemployed with very satisfactory results in No. 0 W001 cut from harddrawn copper or brass wire. The commercial copper wire most easilyobtainable has a certain amount of springiness and the cutting processresults in a copper metal wool which is quite springy. Preferably, I usethis in the condition in which' it comes from the knives, although forcertain purposes it may be softened by annealingor may be freed from afilm of lubricant WhlCll it may acquire during the cutting process, whenlubricant is used to prevent heating of the knives.

As an illustration, No. 0 copper metal wool referred to above, in theuncleansed and unannealed condition, may be packed or wadded into a moldhaving the shape of the desired article and subjected to pressuressuflicient to bend, set and pack the metal into a solid body of thedesired shape. The amount of pressure applied may be varied within widelimits but is usually high and frequently is of the order of pressuresemployed for stamping or die shaping metal articles. In certain cases,particularly with the softer materials, the pressure may be great enoughnot only to set the fibers in intimate relation, but also to causeincipient or partial welding at more or less distributed points in themass.

In most cases thepressure is such as to produce a peculiarly novel metalarticle possessing a porous structure and which is noticeablycompressible and resilient, al-' though the structural strength may beso great that the article will maintain its form and dimensions underrelatively heavy stresses.

Suchfibrous solid, when made up in the form of bearings, either forslide surfaces 1924. Serial No. 718,476.

ite without oil may contribute materially to the solidity and strengthas well as the smooth surface finish of the completed article.

As above stated, the articles may be molded to any desired shape toafford an anti-friction bearing surface between slidlng, oscillating,rotating or other relative motion. It is particularly adapted for use inthe form of oilless bearings for shafts either as a substitute for or incombination with the ordinary bearing. It is particularly useful asbushings for the shafts of small motors or other machinery.

Another important use is as a packing material where a shaft has toproject through a bushing or one or both sides of which may be materialsthat are absorbent of oils as, for instance, ammonia in refrigeratingmachines.

In the forms which depend on graphite and not on a liquid oil film forlubrication, it is particularly adapted for wet bearings, that is,bearings WlllCll are normally immersed in water or other liquids whichwould ordinarily dilute, absorb or dissolve an oil film. For the samereasons, these embodiments of the invention are useful in connectionwith surfaces which are exposed to high temperatures and these maybesubstantially above the temperatures at which oil would vaporize.

An illustrative embodiment of my invent1on may be more fully understoodfrom the following description in connection with the drawings, in whichFig. 1 is an axial sectional view, indicating more or lessdiagrammatically one form of mold that may be used for producing oneform of the article,

Figs. 2 and 7 are side elevations indicating in a general way thematerial from which the article may be made;

Figs. 3 and 4 are respectively edge and face views of an annular bearingembodying one form of my invention;

Figs. 5 and 6 are similar views of a modification.

In these drawings the external cylinder 1, base 2 and core or mandrel 3constitute the female die having the cylindrical annular cavity 4 inwhich fits the annular plunger 5. The metal wool may be packed into thespace 4 in any desired Way, preferably facilitated by some sort of aguide as 6. One convenient Way is to shape the material in the form of acylinder 7 of relatively loose metal wool which may be forced by hand orotherwise over the point 8 of mandrel 3 and into the cavity 4, the loosestructure of the metal wool mass permitting easy penetration by saidpoint 8. Desired pressure is then applied to the plunger 5 to compressthe mass to the final form shown in Figs. 3and 4. The amount ofcompression may be greatly varied, but preferably a powerful press ofany known or desired type will be employed.

Instead of simply wadding the material into the space 4 or perforatingit on cylinder 3, it may be roughly carded in lengths of proper diameterfor coiling down in the annular space 4.

In Figs. 3 and 4 an attempt is made to illustrate a visibly fibroussurface that may be produced when copper wool is used without any filleror binder such as graphite. The visible inequality of the surfaces maybe very greatly decreased by burnishing the surfaces by sliding movementeither in the forming die or in the finishing die which may be employedfor the purpose.

[In Figs. 5 and 6 an attempt, is made to show that when the graphite orother filler is used, the surfaces may be very definite and very smooth,merely from the sliding movement of the metal wool along the walls ofthe die during compression.

When graphite is used, it may be dusted onto the metal wool while in aloose state and the latter may be moistened eitherto the slight degreeit is naturally moistened by the lubricant employed in the cuttingprocess or a special liquid, either of an oily nature or of a volatilenature, may be employed. If Vaseline or grease is used, it is preferablyapplied hot so' as to be as liquid as possible inprder to avoid excess,and various other expedients may be employed to squeeze out excess orproperly determine the amount of the various lubricants or binders thatmay be used.

Plastic clay or cementitious material may I be employed where very rigidarticles are required. In such case, .the binding or cementitiousmaterial may furnish the desired hardness, while the metal wool willconstitute metallic reenforcing analogous to reenforced concrete.

While I have referred to a modification employing metal of suchcharacter and subjecting it to such great pressure as may cause more orless welding of the fibers at the points of intimatecontact, it will beunderstood that in most cases there is no welding, the structuralstrength particularly the tensile strength of the article being onlythat derived from intermeshing and set of the metal fibers. Insome casesthe solidification is evidenced mainly by resistance to compressionstresses and an important feature of the resistance in such cases isthat it is resilient because afforded by what amounts to a mass ofhair-like springs compacted so that the individual fibers have taken aset in all sorts of shapes but most if not all under a substantialremnant of spring stress. It may be imagined, therefore, that when anyone fiber of a wear surface becomes worn through, it results in twominute, free-springing endsthat may easily contribute far more support.-to a shaft or other element carried thereby, than would the originalunsevered loop or length of the fiber. Thus, the bearing is not onlyinitially resilient but also it is, within limits, self-restoring asagainst wear.

In most if not all the preferred forms, the resilient nature of thearticle makes it a poor conductor of sound and other vibrations. Hencethe bearings tend to be noiseless as well as anti-frictional.

As the range or distance of yield, as well as the power of resilientresistance and restoration, are controllable by varying the pressure andextent to which the article is compressed in the making, the product maybe made suitable for cushioning in various connections, for instance, insituations where a relatively'rigid positioning is required but solidunyielding contact of metal on metal is undesirable because of damagingmechanical vibration that may be transmitted from one of the parts to'the other.

I claim:

1. As an article of manufacture, a ma terial including as an essential afibrous mass of springy metal Wool composed of resilient fibersretaining their resilience under stress compressed and having its fibersset to maintain solid form.

2. As an article of manufacture, a material including as an essential afibrous mass of springy'metal wool composed of resilient fibersretaining their resilience under stress compressed and having its fibersset to maintain solid form and with a lubricant in the interspaces.

' 3. As an article of manufacture, a material including as an essentiala fibrous mass of springy metal wool composed of resilient fibersretaining their resilience under stress compressed and having its fibersset to maintain solid form and with graphit-ic material in theinterspaces.

4. An article including as an essential a fibrous mass of intermeshingspringy metal Wool fibers composed of resilient fibers retainin theirresilience under stress 00mpresse and with the fibers set in the shapeof the desired article, the fibers being of a springy metal of a.hardness equal to or less than that of brass.

5. An anti-friction bushing including compressed springy metal woolcomposed of resilient fibers retaining their resilience under stress ofa soft or non-abrasive metal of a hardness equal to or less than that ofbrass molded by pressure into a compact solid.

6. An anti-friction bushing including conipressed springy metal Woolcomposed of resilient fibers retaining their resilience under. stressmingled with a lubricant and molded by pressure into a compact solid.

7. An anti-friction bushing including compressed springy metal woolcomposed of resilient fibers retaining their resilience under stressmingled with graphite and molded by pressure into a compact solid.

8. An anti-friction bushing including compressed springy metal woolcomposed of resilient fibers retaining their resilience under stress ofa soft or non-abrasive metal of a hardness equal to or less than that ofbrass mingled with graphite and molded by pressure into a compact solid.

9. An anti-friction bushing including compressed springy metal woolcomposed of resilient fibers retaining their resilience under stress.

Signed at New York city in the county of NewYork, and State .of l ewYork this 6th day of June A. D. 1924.

CROSBY FIELD.

